In some areas, the predominant method of delivering a television signal is by terrestrial broadcast. The broadcast signal is then received by viewers using an antenna connected to a television set. This broadcast signal will be strong near the transmitter and then get weaker with distance. The broadcast signal will also get weaker due to physical obstructions that occur between the transmitter and the viewer's antenna. In areas where the broadcast signal is weak or subject to strong multi-path signals, the antenna may be mounted on a rooftop or other exterior location for improved reception. A wire or cable then transmits the signal received by the antenna indoors to the television set.
For optimal operation, the exterior antenna should generally be at least a particular minimum size. However, for aesthetic reasons, homeowners and other building owners may opt for a smaller, less obvious exterior television antenna. Unfortunately, as the exterior antenna is made smaller, reception quality is sacrificed. In particular, if the antenna is smaller than the optimal size, the result may be reduced gain, poorer front to back rejection, more side lobes, poor impedance matching, etc.
However, antenna designers and manufacturers can often trade on one more of these parameters, while still maintaining sufficient performance in the remaining parameters. For example, gain can be sacrificed while still maintaining generally good reception, even with a shorter antenna boom length.